@vdubrox,
Your other thread indicated that you two are trying to move on but still were trying to keep in touch. Perhaps the strain of doing this was too great for him. You may really need to let go. If he wants to return to you as a friend, then you need to give him the space. Try not to fixate on the past, for your own sake.
This hurts now, but you'll heal better if you don't allow all of your thoughts about the past dominate your head and heart.